1. Field of the Invention
This invention relates to blind rivets and particularly blind rivets having a large secondary head.
2. Statement as to Prior Art
There are a number of different types of blind rivets on the market which have a hollow rivet body with a flanged head on one end and open on the opposite end. A mandrel stem is adapted to pass through the opening in the body of the rivet with the mandrel stem having an head positioned adjacent the open end of the rivet body. The rivet body can then be inserted into the opening in a workpiece with the flange of the rivet lying flat against the surface of the workpiece. The nosepiece of a rivet setting tool is placed against the flange of the rivet body and by pulling the mandrel, the rivet body opposite the flange is upset by the head of the mandrel on the opposite side of the workpiece to form a secondary head on the rivet body thus, securing the rivet to the workpiece. This process is generally known in the art as "setting" the rivet. A continued pulling force on the mandrel stem will break off the mandrel stem from the mandrel head permitting removal of the mandrel stem from the rivet. In this manner, the rivet is secured in the opening in the workpiece with the flange of the rivet against one surface of the workpiece and the formed secondary head against the opposite surface of the workpiece.
Examples of rivets of this type and tools for setting the rivets are illustrated in U.S. Pat. Nos. 3,254,522; 3,302,444 and 3,324,700.